Method and apparatus for yarn processing



. i 19, 1946. FYR, MILLHISER 2,395,136

METHOD AND APPARATUS FOR YARN PROCESSING Filed Jan. 9 1942 ATTORNEY Patented Feb. 19,1946

2,395,136 a METHOD sun arraasrus son man raocassmo Frederick a. mum, Chesterfield County, Va.,

assignor to E. L du Pont de Nemours & Company, Wilmington, er, a corporation of Delas ue uon January 9, im. Serial No. 428,184 Claims. (01. zs-us) invention relates to a method and apparatus for imparting an impelling, directional force to a yarn. More particularly; the invention relates to a method and apparatus for imparting a sufiicient impelling, directional force to a yarn to positively forward the same which force will,

tension to theyarn.

In numerous methods for the production or processing of rayon yarn, it is essential that the yarn be forwarded in a uniformly controlled positive manner but without imparting any appreciable amount of tension to the yarn.

It is, therefore, an object of the present invention to Provide an-improved method and apparatus for posltivelyimpelling a yarn in a uni! formly controlled manner without imparting substantial tension to the yarn and without disarranging the parallel filaments in a yarn. Other objects of the invention will appear hereinafter.

In accordance with the present invention an impelling force is imparteddso a yarn y positioning the yarn between the converging walls of .a

. substantially V-shaped groove anddirecting an impelling stream of liquid against the yarn positioned between said converging walls. To prevent undesirable disarrangement of the illaments'by flooding of the yarn, and to provide sufficient impelling force by the liquid, the above-said stream of liquid should have a mass per unit of time between three and fifteen times the mass of yarn passing through the groove within the same unit of time. The velocity of the stream should be greater than the impelled speed of the yarn, and preferably it should be at least two times the impelled speed of the yarn.

The details of the present invention-will be more clearly apparent by reference to the following description when taken in connection with the accompanying illustration, in which:

Figure 1 is a perspective view of a device constructed in accordance with the present invention.

Figure. 2 is a partial cross-sectional view through the apexof the V-shaped groove shown in Figure 1. 1

Figures is a side elevational view, with parts shown in perspective, illustrating one application of apparatus constructed in accordance with the present invention.

however, be insuflicient to impart an appreciable I of V -shaped groove for a yarn-impelling device constructed in accordance with this invention.

Referring to'the drawing, reference numeral ii designates, generally, a yam-impelling device as hereinafter described in detail. The device Ii comprises a plate I: provided with a V-shaped groove ii. A supporting bracket I1 is connected to plate It. The supporting bracket H has a ledge 19 slightlyoverhanging the plate It. A nozzle ii is positioned in the ledge l9. The noz- .zle is provided with a fine tubular point 23 which is directed atran acute angle against' the uncut juncture of the converging walls of the v-shaped groove II. This is clearly shown in Figure 2 of g the drawing.- It will be here noted that in accordance with the preferred construction, the fine tube 23 is positioned at an angle of about 20 to the vertical rear wall of the notch. A liquid supply conduit 25 is connected to the inlet side of the nozzle, and a pump 21 is 1 connected tothe conduit to pass a liquid under pressure therethrough. A yarn 28 is positioned between the converging walls of the V-shaped groove ii. The liquid passing from the fine tubular point 23 of the nozzle will then be directed against the yarn and toward the line of juncture of the converging walls of the V-shaped groove. As shown in Figure 2 of the drawing, the liquid will pass against the yarn in the apex, or bottom, of the groove substantially at the point 3| thereby causing the yarn to-be impelled along the bottom of the groove in the direction of the arrow. The stream of liquid will also cause the yam to be maintained in the bottom of thegroove.

' mately witheaoh other, the walls of the groove Figure 4 is a perspective view of. two rmf impelling devices, construct d in accordance with view of a modified form In accordance with the preferred constructio of the present invention the grooved plate It and the tubular point 23 of the nozzzle will be positioned at such an angle to each other that the stream of liquid issuing from the nozzle will impinge in a downward direction on the lower portion of the line of juncture of the converging walls of the V-shaped groove It. The grooved plate ills preferably constructed of a corrosionresistant alloy having a thickness of approximately inch. The groove it in the plate is preferably of such a shape that the convergin walls of the groove form an angle of approxibeing ormal to the flat top and bottom surface of the plate 13. The tubular point 23 of the nozzle preferably comprises a platinum tube of about flinch in lengthand having an internal .diameter of about 0.011 inch.

Referring to Figure 2 of the drawing, it will be noted that the plate It in which the groove I! is i formed is made of gradually increasing thickness. This has been done to increase the angle between the yarn passing from the plate and the bottom of the plate. This angle should be at least 90.

Figure 3 of the drawing illustrates a yam-pro- 5 of overlapping ringlets.

ducing apparatus of the general type disclosed ir\ British Patent No. 379,880. The yarn 29 is removed from the coagulating and/or regenerating bath by means of a feed wheel comprising ieed roller 33 and cooperating yarn-separating roller 35. The yarn 29 is generally passed a plurality of times about said rollers to prevent slippage when a comparatively high tension is applied to the yarn in the spinning bath. The yarn 29 is then directed to a slowly moving belt designated by numeral 31. In accordance with the above-said British patent process, theyarn is to be collected by the belt 3'! in acompletely relaxed condition. If the yarn is merely dropped to the belt from the separating roller 35, there will be a tendency of the yarn to cling to roller 35 and possibly wind up on said roller. In order to feed the yarn from the rollers 33 and 35 to the collecting belt 31 without imparting substantial tension to the yarn, a plate member l3 containing a V-shaped groove I5 is positioned adjacent the belt 37. The yarn Z9 is positioned in the bottom of the V-shaped groove and a nozzle 2! is positioned to direct a stream of liquid against the bottom of the groove in the direction of the movement of the thread. The yarn will thereby be prevented from clinging to roller 35 and will be caused to drop in a substantially free and completely relaxed condition on to the belt It is preferred that the yarn passing into the bottom of the groove i5 have an angle of substantially 10 with the line defining the bottom of the groove. thus imparted to the yarn aids in properly positioning the latter in the groove and aids in holding thefsame under the influence of the impinging stream of liquid. .Although the angular path of the yarn from the roller 35 to the groove l5 somewhat retards the advance 'of the yarn through the guide, this is of relatively minor importance compared to the advantage accruing from the provision of the angular path of the yarn.

The grooved plate 113 is preferably positioned about 1 to 2 inches above the conveyor belt, al though this distance 'may vary from A to 6 inches. The belt may be mounted almost any desired distance below the feed wheel. It can, if desired, be mounted within one foot below the feed wheel; however, for purposes of practical design and to insure adequate head room, it is .which overlap each other as the yarn-impelllng devices are traversed transversely of the belt. For the purpose of obtaining a transverse movement of the yarn-impelling devices, they may be attached to a traverse bar 43 which is reciprocated by mean of the cam 45. The movement The slight angular tension Referring to the modification shown in Figure 5 of the drawing, the plate I3 is provided with a'V-shape'd groove i5 having a slightly rounded apex or bottom 56. This form of device may be used when impelllng a heavy denier yarn; that is, a yarn having a denier of 1100 or greater.

Because of the positioning of the tubular point 23 of the nozzle at an acute angle to the line of juncture of the walls of the V-shaped groove iii, the stream of liquid striking the yarn positioned within the bottom of the groove serves at once to direct. the yarn through the groove and to maintain it positioned against the apex or bottom of the groove. Thus, this impinging stream of liquid subjects the yarn to an impelllng force which is of very slight but inappreciable tension. The tension will, of course, be sufilcien'; to prevent the wrapping of the yarn about the feed roller or separating roller as shown in Figure 3 of the drawing. The V-shaped groove supports the yarn and serves to hold the advancing yarn in position and keep it constantly under the influence of the downwardly directed force of the liquid. The magnitude of the downwardly directed force imposed on the yarn by the liquid stream is dependent on the totalmass and the velocity of the stream, and upon the angle at which it strikes the yarn positioned in the bottom of the groove. It is preferred that the stream of liquid be very fine so that undue flooding of the yarn will be avoided. Preferably, the stream of liquid issuing from the nozzle per unit of time should have a mass from three to fifteen times the total mass of yarn passing through the guide within the same unit of time. If the ratio of liquid to yarn mass is less than three, the stream will not possess suflicient driving force to impel the yarn with a uniformly controlled force. if the ratio is greater than I5, the stream will flood the yarn and thereby cause the filaments oi the yarn to be deranged and possibly damaged.

The processand apparatus of the present invention is preferably operated with the advancing yarn passing in a vertically downward direction; however, it can also be used in processes where the yarn is directed at substantially any angle to the vertical. In fact, apparatus constructed in accordance with the present invention i capable of directing an advancing yarn or- 150-denier in a horizontal, or even upward, direction for a distance of several inches. v

The dimensions and operation of the device of the present invention will, of course, depend somewhat upon the denier and spinning speed of the yarn. For example, as the denier is increased or the spinning speed is increased, it will be preferred to increase the impelllng force of the impinging stream of liquid. This may be done by increasing the pressure on the liquid so as to i crease both the mass and velocity of the stream. Alternatively, the inner diameter of the nozzle may be decreased and the pressure maintained constant or increased. In any event it is necessary that the stream possess a velocity that is always slightly greater than the yam speed and preferably at least two times the yarn speed. Obviously, many possible combinations'of nozzle diameter and liquid pressure can be employed to obtain any desired relationship to the denier and speed of the yarn. In general, satisfactory redownwardly in a straight line.

sults can beobtained by using a nozzle having an inner diameter of the order of 0.011' inch and varying the pressure. However. the invention contemplates the use of nozzles having a diameter of from 0.005 to 0.02 inch which will impart the ve-' locity and massof liquid referred to above.

In general, the nozzle or the tubularpoint thereof should be mounted as close to the apex of the grooved plate it as is practical, preferably within V inch. By thus positioning the nozzle close to the apex of the groove, the liquid will impinge on the yarn as a fine stream and the tensioning eflect of the liquid on the yarn will actually serve to hold together, in a compact bundle, the filaments comprising the yarn. If the nozzle is spaced from the apex 'of the groove a materially greater distance than ,6 inch, the stream, because of itsv small mass, will separate into small individual droplets, and its velocity will be greatly decreased. Thus, its efficiency in directing the advancing yarn will be greatly diminished.

when used in connection with the spinning of tained it the impelling liquid forced through the nozzle is of the same composition as the coagulating bath employed in the spinning process.

' 10,000 inches per minute.

minimum of tension and without causing heading of the yarn. It is particularly valuable in those cases 'where the yarn-collecting means exertsno directiveor pulling force on the yarn. I

The present invention finds particular utility in connection with the spinning of yams at high speeds, that is, speeds of the order of 8,000 to Nevertheless, the invention can also be used to advantage with low spinning speeds of the order of 3,000 inches per minute.

be impelled with a uniformly controlled force viscose rayon yarn, desirable results will be-ob- Nevertheless, water or other liquids can also be stream to exert a much greater force against the By means of the present invention, a ya "1 can without imparting an appreciable tension to the yarn, and without causing a flooding of the yarn.

Since it is obvious that many changes and modiiications can be made in the above-described de- 1 tails without departing from the nature and spirit of the invention, it is to be understood that the invention is not to be limited to the details described herein except as set forth in the appended claims. l

I claim:

1. A yarn impelling device comprising-a mem-,

her having converging walls forming a substantially v-shaped groove, a nozzle spaced from said 4 groove, said nozzle directed at an acute angle toward the line of juncture of said converging walls, said device being adapted to receive a yarn adjacent said line of juncture of said converging walls, and means for passing a yarn impelling groove. The materials of the deviceof the pres-, ent invention may be made of substantially any non-corrosive metal, or of a suitable plastic material or ceramic material) A desirable composition of the grooved plate comprises a fused titanium oxide product sold under the trade name Alsimag."

As above referred to the angle between the descending yarn passing from the bottom of plate I! and the bottom of the plate should be at least 90. 'Ihis angle is designated in Figure 2 as angle .11. If this angle is materially less than 90, the descending yarn tends to cling to the lower surface of the groove rather than to be impelled stream through said nozzle against said yarn.

2. In a device as defined in. claim 1 in which said line of juncture does not exceed 4, inch in length.

3. In a device as defined in claim 1 in which said line of juncture forms an angle of atleast 90 to the surface of said member from which 6. A method of imparting a uniformly controlled impelling force to a yarn which comprises positioning a yarn against a surface, and directing a stream of liquid at an acute angle against said yarn and toward said surface as the sole means to move the yarn along said surface, said centrifugal bucket, the device of the present invention can satisfactorily be mounted above thereciprocating funnel guide of a bucket spinning apparatus, and the device will serve to guide the 1 casewhereitisdesiredtodirectayai'nwitha.v

stream having a velocity exceeding the linear velocity of said yarn, and having a mass" per unit of time between 3 .and 15 times the mass of yarn passing along said'suriace per unit of time. 'I.v The method as defined in claim '5 in which the acute angle'is about 20.

' 8. The method as-defined in claim 5 in which said liquid is water. a

9. The method as defined in claimfi in which the liquid is a coagulating liquid for said 10. The method as. defined in claim 5 in which the velocity of said liquid is at least two times the velocity of said yarn. 

